Hemoglobin S

Hemoglobin S (HbS) is an abnormal form of hemoglobin associated with sickle cell disease. This test detects the presence of HbS using electrophoresis. Hemoglobin S polymerizes under low-oxygen conditions, causing red blood cells to assume a sickle shape, which damages blood vessels and organs. The test distinguishes between sickle cell disease (two HbS genes), sickle cell trait (one HbS gene), and normal hemoglobin. Sickle cell disease causes pain, organ damage, and shortened lifespan. Early detection enables disease monitoring and preventive treatments. Screening is especially important for people of African, Mediterranean, or Middle Eastern descent.